Add a JavaScript display to the Home page to count down from 140 characters. (Rails Tutorial, 2nd Ed, Chapter 10, Exercise 7)

Question

This exercise was a bit tricky. Figured I\'d post my solution to see if anyone did it differently or if there\'s anyone who knows a better way.

I\'m not sure on best pra

Answer 1

My microposts.js.coffee uses the jQuery .css method to change the color of the characters remaining based on the value of the variable remaining to more closely mirror the behavior of twitter

updateCountdown = -> 
  remaining = 140 - jQuery("#micropost_content").val().length
  jQuery(".countdown").text remaining + " characters remaining"
  jQuery(".countdown").css "color", (if (140 >= remaining >= 21) then "gray")
  jQuery(".countdown").css "color", (if (21 > remaining >= 11) then "black")
  jQuery(".countdown").css "color", (if (11 > remaining)  then "red")

jQuery ->
  updateCountdown()
  $("#micropost_content").change updateCountdown
  $("#micropost_content").keyup updateCountdown

Thanks to all who answered before.